High cholesterol increases your risk of heart attack. More than 100 million people in the United States have high blood cholesterol, according to the Centers for Disease Control and Prevention, and 35 million of these Americans have levels high enough to put them at risk for developing heart disease. Understanding the risks associated with the different types of cholesterol may reduce your chances of suffering a potentially life-threatening cardiac event.
Types
Cholesterol is insoluble in blood so it is carried to the cells by lipoproteins. Low-density lipoprotein, or LDL, is the type of cholesterol most closely associated with heart disease. Because it is denser, high-density lipoprotein, or HDL, scrubs LDL from the inside of arterial walls and carries it back to the liver where it is excreted along with other wastes. HDL lowers your risk of heart disease by reducing the amount of LDL along arterial walls.
Function
A poor diet along with low HDL and other factors such as smoking, obesity and a sedentary lifestyle causes LDL cholesterol levels to build up in the bloodstream and accumulate on the inside walls of arteries, which are normally strong, flexible and elastic. This accumulation can harden into plaque, which causes the arteries to grow thick, hard and less flexible. Build-up of cholesterol and plaque in the arteries is called atherosclerosis, and hardening of the arteries is known as arteriosclerosis, although MayoClinic.com notes the terms are often used interchangeably.
Risks
Arteriosclerosis narrows the arteries and impedes blood flow. If arteriosclerosis is near the heart, blood may be prevented from reaching the muscles of the heart, resulting in chest pains or even heart attack. Blockages near the brain can result in stroke. Arteriosclerosis can cause peripheral artery disease, which causes circulation problems in the arms or legs. Plaque can rupture, or tear away from arterial walls, and the body may react by creating a blood clot over the area where the plaque had been. This clot can break free and become lodged in an artery, preventing blood flow from reaching the muscles of the heart, potentially resulting in a heart attack.
Identification
A blood test measures the amount of HDL and LDL in the blood. The best HDL level for preventing heart disease is 60 mg/dL or above, according to Lab Tests Online.org. Men whose HDL is below 40 mg/dL and women with levels below 50 mg/dL are at increased risk for heart disease. Healthy LDL levels measure below 100 mg/dL. LDL levels between 160 and 189 mg/dL are considered high.
Prevention
Smoking, obesity, a low-fiber diet high in sugar and fat and a sedentary lifestyle lead can all contribute to high LDL cholesterol levels and reduced HDL. Losing weight, eating a nutritious low-fat diet full of fresh vegetables and whole grains, exercising and smoking cessation, along with medications, can lower LDL cholesterol levels. Increasing HDL levels is also an effective strategy, and the B vitamin niacin has been shown to be effective at increasing HDL, according to the Mayo Clinic. As with all such changes to diet and medication, check with your physician before taking niacin and making other changes to improve your diet.
